Influence of Fogging Lenses and Cycloplegia on Peripheral Refraction

Abstract

PURPOSE:To compare objective peripheral refraction measured with an open-field autorefractor without cycloplegia with the values obtained with fogging lenses or with cycloplegia to inhibit accommodation. METHODS: For one hundred and sixty young adults aged 18 to 28 (mean 21.5 ± 2.3 years) their refraction was measured with the Grand Seiko (GS) autorefractor at the center and at four peripheral locations in the nasal and temporal directions under three different conditions: 1) without cycloplegia (GS); 2) without cycloplegia, but using a +2.00D fogging lens (GS_2D) and 3) with cycloplegia (GS_cycl). RESULTS: Mean spherical equivalent refraction (M) was significantly more negative with the GS method in the hyperopic group for central and peripheral refraction, and only at the center and at 10º nasal eccentricity for the emmetropic group (P<0.05, KruskalWallis). Paired comparison showed that differences of M values across techniques were larger for the GS-vs.-GS_2D comparison in myopes and emmetropes, and for the GS-vs.-GS_cycl one in hyperopes (P<0.001, Wilcoxon Signed Ranks Test). The gap between M values for all paired comparisons remained almost constant across all eccentric positions under analysis. CONCLUSIONS: Fogging lenses used with open-field autorefraction up to 20º in the nasal and temporal fields seem to provide similar accommodative relaxation to that provided by a cycloplegic. This is particularly important when refracting emmetropes and hyperopes. Moreover, this behavior seems to be independent of the eccentricity at which measurements are taken. RESUMEN OBJETIVO:Comparar las medidas objetivas de refracción periférica realizadas sin cicloplégico con los valores obtenidos con "lentes de miopización" o con cicloplegia, ambas técnicas utilizadas para inhibir la acomodación. MÉTODOS: Se midió la refracción a 160 adultos jóvenes, con edades comprendidas entre 18 y 28 años (media=21,5± 2,3 años), con un autorrefractómetro Grand Seiko (GS), tanto en el centro del campo visual como en 4 regiones de la periferia situadas nasal y temporalmente, y todo ello en 3 condiciones diferentes: 1) sin cicloplegia (GS); 2) sin cicloplegia , pero utilizando una lente translúcida de +2.00 D (GS_2D) y 3) con cicloplegia (GS_cycl). RESULTADOS: La media del equivalente esférico de la refracción (M) resultó ser significativamente más negativa en la condición GS en el grupo de los hipermétropes en lo que respecta a refracción central y periférica, mientras que en el grupo de los emétropes sólo ocurrió esto en el centro y a una excentricidad de 10º nasal (P<0,05, Kruskal-Wallis). La comparación por pares de muestras relacionadas reveló que la mayor diferencia de M entre distintas condiciones se obtuvo al comparar GS y GS_2D en el grupo de los miopes y en el de los emétropes, y al comparar GS y GS_cycl en el de los hipermétropes (P<0,001, contraste de Wilcoxon de rangos con signo). La discrepancia entre valores de M para las distintas comparaciones por pares se mantiene prácticamente constante para todas las excentrici...

Changes in Peripheral Refractive Profile after Orthokeratology for Different Degrees of Myopia

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Peripheral Refraction in Myopic Eyes After LASIK Surgery

“…This instrument has been previously used and validated to measure refraction in the central 21 and peripheral visual field. 22 The system was attached to a custom software developed to automatically record data from the autorefractometer thus avoiding errors in data collection and allowing rapid acquisition to be processed in an Excel spreadsheet for later statistical analysis.…”

Peripheral myopization and visual performance with experimental rigid gas permeable and soft contact lens design

“…The measurement of central and peripheral (off-axis) refraction were obtained with an open-field Grand Seiko Auto-Refractometer/Keratometer WAM-5500 (Grand Seiko Co., Ltd., Hiroshima, Japan) up to 30 • in the nasal and temporal horizontal field in 5 • steps. This instrument and its other commercial brand using the same technology for refractive error measurement (Shin-Nippon) have been reliably used in foveal [21,22] and peripheral refraction measurements [10,23]. For the purpose of this study, a laser system was mounted on top of the subjects head and aligned with the central fixation point in primary gaze.…”

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